The invention generally concerns the communication of additional information in close association with a telephone connection. Especially the invention concerns the use of such communicated information for providing added value to the telephone connection.
In many cases there exists a need for transmitting, in close association with a telephone connection, other information than the simple request for call connection and the subsequent voice and/or data transfer. The additional information may be for example in the form of relatively short character strings, where xe2x80x9crelatively shortxe2x80x9d means strings containing usually some tens of characters, or some hundreds at most. Other types of additional information comprise (but are not limited to) binary messages and short executable instructions transmitted between digital computer devices.
In a very simple example it has been found useful to inform the intended recipient of a telephone call about the identity of the caller. A known solution for this task is to communicate, in digital telephone systems, the Calling subscriber Line Identity or CLI number of the caller""s telephone to the intended recipient""s telephone as a part of the message that indicates the incoming request for call establishment. Known ways for utilizing the received CLI number at the receiving end are displaying it to the user, converting it to a name or other alphanumeric identifier fetched from a memory and displaying the conversion result to the user, comparing the CLI number to a list of preprogrammed identification rules and selectively refusing or accepting the call depending on the comparison result, or selecting a preprogrammed ringing tone according to who is calling.
The drawbacks of the CLI application relate to the fixed relationship between the CLI and a certain mobile station (in mobile telephone systems) or telephone plug socket (in fixed telephone systems). The CLI number has no direct relationship to he actual caller; it only identifies the hardware he is using. In many mobile telephone systems the CLI is stored in a removable SIM or Subscriber Identity Module that was originally meant to be strictly personal, but in practice the xe2x80x9cauthorisedxe2x80x9d or documented user of such a mobile telephone+SIM combination always lets other people use the telephone without requiring them to use their own SIM. Another drawback is that the CLI number is seldom informative enough to add a significant amount of value to the call.
A known way of communicating relatively short character strings without an association to a telephone connection is the use of Short Message Services or SMS. Certain digital telephone systems like the GSM (Global System for Mobile telecommunications) allow the users to transmit and receive SMS messages that traverse the network in the form of signalling and do not require the establishment of a call connection. The transmitting user may compose each SMS message freely within the available character set, so they are very well suited for customised communication. However, it is just their independency of call connections that makes SMS messages slightly unpractical for transmitting strictly call-related information. Irrespective of whether a user is placing a call or not, he must initiate the SMS mode separately. Additionally the system will usually give no guarantees about the delay it takes before a transmitted SMS message reaches its destination.
From the technology of Private Automated Branch Exchanges or PABXs and from numerous other applications there is known the transfer of numerical character strings in the form of Dual Tone Multifrequency (DTMF) sequences. A user may transmit a number or a string of numbers by manually pressing the corresponding numerical keys in a telephone, which transmits the standardised characteristic dual audio tone combination on each keystroke. The receiving PABX or other device interprets the numerical sequence and uses the interpreted information in taking some further action. In a typical application the PABX belongs to an insurance company or other enterprise with a very large computerised customer database, whereby the calling customer gives his customer identification number as a DTMF sequence and the PABX searches and displays the customer""s file on the screen of the person who is going to answer the call. This method is limited to the transmission of numerical information and requires a DTMF encoder in the transmitting device and a correponding DTMF decoder at the receiving end. Additionally it necessitates always the full establishment of a telephone connection before the transmission of numerical strings becomes possible.
It is an object of the present invention to provide a method and an arrangement for the transmission of call-related information, avoiding the above-described drawbacks of the prior art solutions. It is a further object of the invention to present a method and an arrangement for using the transmitted information for providing added value to the users taking part in the telephone connection.
The objects of the invention are achieved by using user-to-user signalling for transmitting call-related information, and by defining certain practices for handling the user-to-user signalling messages.
The method according to the invention is characterised in that it comprises the steps of
transmitting from a first telecommunication device to a second telecommunication device a request for setting up a telephone connection,
transmitting, from one of said first and second telecommunication device to the other, a first signalling message associated to the call the setting up of which was requested by said request, and
making a decision about how to handle the call the setting up of which was requested by said request, on the basis of the information received in said first signalling message.
The invention also applies to a telecommunication device comprising a memory, a processing unit, a transmitting unit and input means. It is characteristic to the device according to the invention that as a response to a command given by a user through the input means, said command indicating the user""s wish to place a call to a certain telephone number, the processing unit is arranged to
transmit to said telephone number a request for setting up a telephone connection,
read previously stored information from said memory, and
transmit to said telephone number, through the transmitting unit and in association with said request for setting up a telephone connection, a first signalling message carrying the information read from said memory.
User-to-User signalling or UUS is a procedure recently disclosed as a supplementary service in some advanced telephone systems. Its inteded use is the transmission of a limited amount of subscriber generated information (UUI; User-to-User Information) to and/or from another user in association with a call between the users concerned. The nature of UUS dictates that the network that mediates the communication between the users does not interpret the UUI or act upon it in any way, i.e. it is passed xe2x80x9ctransparentlyxe2x80x9d through the network. This patent application will refer to the known aspects of UUS in the form in which they have been disclosed in the document xe2x80x9cGSM 02.87: GSM Digital Cellular Telecommunications System (Phase 2+); User-to-User Signalling (UUS); Service Description, Stage 1, v.5.2.1xe2x80x9d, which has been published by ETSI (European Telecommunications Standards Institute) in November 1997.
According to the invention, UUS is used to convey certain caller- and/or receiver-related information between the calling party and the called party in the beginning of a call, during a call and/or at the end of a call. The transmitted information is used in the other end to manually and/or automatically evaluate some features that are helpful in deciding how to handle the call.
In a first embodiment of the invention the calling party (known as xe2x80x9cAxe2x80x9d in the common telephone jargon) transmits manually and/or automatically some additional information about him/herself to the called party (xe2x80x9cBxe2x80x9d) at the call setup phase or during the call. In this context, xe2x80x9cadditionalxe2x80x9d means such information that does not form a part of a routine call setup request like the CLI number. At the receiving end B may use this information for directing A""s call to a certain person or certain extension or for identifying and retrieving previously stored data from a database. The invention does not set any limits to the nature and content of the information transmitted by A. It may be a routine message transmitted at the setup of each new call, or the transmitted information may be selected according to the identity of the called party.
In an advanced variation of the first embodiment of the invention A is a remote user of a restricted data system (B) and the information transmitted at the call setup phase contains a password or other classified identifier that the data system uses to check A""s authorisation for using the system. A positive identification causes B to place a call back call to A for the establishment of a data transfer connection, and in negative cases B simply rejects the attempted call.
The invention does not limit the direction into which information is transferred by using the UUS. In a second embodiment of the invention A is a remote operator responsible for the operation of a computerised system or device. Operation begins with a data call from A to B. B answers either by a call rejection together with a short UUS message indicating the cause of the rejection, or by accepting the call if there is enough data to be transferred to A to justify a data call being set up.
A further embodiment of the invention is applicable in a situation where B is not able to answer A""s call for the moment, but wants to inform A about the reason for him not answering. According to the invention B transmits manually or automatically a UUS message to A informing him about the situation. The selection of the UUS message to be sent may be based on the identification of the calling party.